Uplink on Hub Blinks Rapidly

[LadySlinger]

Hello,

I'm currently switching over a bunch of computers from one network/T1 line to another. When I'm three feet away from the network closet, the new LAN works perfectly. When I plug in a computer that's a little bit further away (try maybe 10 ft) I notice that the uplink port on the hub begins to blink rapidly. I can "talk" with other computers on the network if I plug more in, but when it comes to connecting it to the internet, it doesn't happen.

And yes, I have double checked the IP configurations. Also when I unplug the computer from the the hub, the uplink port continues to blink.

Anyone ever see this?

 

[jimbopalmer]

If you mentioned the brand name/model number we could read the manual and find out what that means. I tried to remain child-like, all I acheived was childish.

 

[LadySlinger]

It's a Linksys NH1005

 

[franklin97355]

When you are three feet away are you using the hub? In other words is everything the same in both instances?

 

[LadySlinger]

Yes, the only thing that changes is the location of the hub (from 3 feet to being maybe 15 - 20 feet away). Same type of cables, same laptop. It's the most bizarre thing I've seen.

 

[smah]

What do you mean 'Same type of cables'? Is it the same cable or not? Under the right conditions, a bad cable could do this.

 

[Grenage]

Indeed, if it is not the same cable. Check the cable crimps and wiring on the other cables. Then replace the cable if it still happens.

 

[LadySlinger]

OK fellas,
I just read up on a "new" type of straight through and cross over cable where the 3 & 6 are crossed on a straight through. The network that is in current use is a good many years old with the typical straight through. And that's why I had the problems.
I had been mistaking this and was an easy error to see.

Thanks though.

Ladyslinger

 

[LadySlinger]

Er...an easy error to miss

Thought I would catch that before i received an English Lecture

 

[daronwilson]

A new type of network where the 3 and 6 pins are reversed on a straight cable? Please share with the rest of us, I've not heard of this.
It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[LadySlinger]

This new industry standard is hard to notice at first until someone points it out:
If you look at a regular straight thru cable you'll notice that all the striped wires are with their corresponding solid wire. For Example,

Orange striped/Orange/blue striped/blue/green stripe/green/brown striped/brown

This is the way the straight thrus are in my current office. The network was set up probably a good 6-8 years ago before I came on board.

well I just found out yesterday of this "new" crossover cable where the green wire is paired up with the blue striped and the blue wire is paired up with the green striped wire. So then,

orange striped/orange/green striped/blue/blue striped/blue/brown striped/brown.

http://yoda.uvi.edu/InfoTech/rj45.htm

 

[smah]

"Orange striped/Orange/blue striped/blue/green stripe/green/brown striped/brown"
This is incorrectly wired

"orange striped/orange/green striped/blue/blue striped/green/brown striped/brown"
This is the correct 568B standard (with green fixed) and is not by any means new and it is not a crossover if both ends are the same.

Here's some very good info about making network cables and how to connect them

http://www.duxcw.com/digest/Howto/network/cable/cable1.htm

 

[daronwilson]

Thanks for sharing with us Ladyslinger, apparently you discovered the correct way to wire patch cables. If the cables in your current office are wired differently than the description on your link, they are non-standard cables.

It is possible someone put the network together and wired the jacks to match the patch cables, I've seen that before where the patch cables were paired similar to your description, and the jacks were miswired as well so that they managed to keep the transmit pair on an actual pair, and the recieve pair on an actual pair. But I've also seen patch cords like you describe with a regular 568B wiring scheme, and lots of trouble.

Usually this happens when someone starts with a 10mbs network and tries to put thing together without really knowing the correct methods. Then years later as they migrate to 100mbs they start noticing the problems.

We've discussed it many times in this forum, but basically you need a pair (white/color) that is twisted together to keep that particular signal from 'jumping' to the signal headed the other way and disrupting communications. Looking at the way wires are in your office currently you have the transmit signal on the white/orange pair, but the receive signal you have one white/blue and green/white. When you 'split the pair' like this you and promote crosstalk between the signals. If you scanned this cable for Cat5 compliance it would quite likely not pass.

Hope that isn't too confusing. It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com

 

[LadySlinger]

Thanks everyone!

I'm not sure why this network was wired this way. I was told earlier on Friday that this was "new". reason why I placed it in quotes when I first mentioned the different wiring schemes and I didn't entirely trust the source of the findings.

In anycase, I obviously did not know that much about the nit & grit of networks (other than plug the cords into the hub or switch and run the network).

So thanks again!
LS

 

[Bobg1]

Hmmm, Ladyslinger in your first post you say that you are working on a network/T1, I suspect what you are actually doing is going from a 10m network to a 100m network.
(a T1 is even slower) The cables as you have described will work at the slower speed and possible a short run on higher speed, bit not at any distance with the higher speed. You might also want to investigate if the installed cabling is cat5, it may only be cat3 if it is old. If it was properly installed cat3 may run at 100, but not reliably.
If you find you have cat3 you will want to make sure you hard set everything you use at 10m, to avoid having problems.